Meta-analyses of the effects of river flow on fish movement and activity

Abstract

Estimating the timing and magnitude of fish movements relative to environmental factors can provide insight into why fishes behave as they do. To make broad-level inferences about fish movement in lotic environments, we conducted random-effects meta-analyses on the effects of river flow magnitude on (i) non-migratory movements, (ii) upstream migratory movements, (iii) downstream migratory movements, and (iv) fine-scale activity. We found a significant positive effect of river discharge on non-migratory movements ([Formula: see text] = 0.41 (mean) ± 0.07 (SE), Z = 6.06, p < 0.01, k (sample size) = 27); fishes made larger and (or) more frequent movements during periods of elevated discharge. Furthermore, non-salmonids were more affected by river flow than salmonids. River discharge also had a significant positive effect on the rate, frequency, and probability of upstream migratory movements ([Formula: see text] = 0.23 ± 0.10, Z = 2.24, p < 0.05, k = 8). However, the effect of discharge on the rate of downstream migratory movements ([Formula: see text] = –0.05 ± 0.15, Z = –0.35, p > 0.05, k = 5) and fine-scale activity ([Formula: see text] = 0.01 ± 0.11, Z = 0.08, p > 0.05, k = 5) were not significant. Heterogeneity of effect sizes was evident in all meta-analyses as well as inclusion and (or) publication bias. Collectively, our meta-analyses suggested that changes to a river’s flow regime can modulate non-migratory fish behaviour, the consequences of which need to be explored in terms of habitat use and energy budgets. However, more studies are needed to examine potential effect modifiers and improve sample sizes overall.

Spatiotemporal patterns of mountain whitefish (Prosopium williamsoni) in response to a restoration of longitudinal connectivity

“…We also observed that annual variation in movement rates through the ladder co-varied with spring-summer discharge and temperature, possibly acting in concert with the physiological status of migrants (Radinger & Wolter, 2014;Skov et al, 2010;Taylor & Cooke, 2012). Consistent with the positive relationship between discharge and mountain whitefish movement we observed, upriver movement of adult coho salmon through the Landsburg Dam fish ladder during their spawning migration was positively associated with river flow and with change in flow from the previous day in two of three study years (Anderson & Quinn, 2007).…”

Flow‐mediated movement of freshwater catfish, Tandanus bostocki, in a regulated semi‐urban river, to inform environmental water releases

“…These results indicate that flow is an important factor influencing the movement patterns of T. bostocki and suggest that environmental flows will be a useful tool to facilitate the natural movement of this species.The strong association between flow and fish movement found in this study is consistent with numerous other studies that have found positive associations between river discharge and the extent and frequency of fish movement (see meta-analysis byTaylor & Cooke, 2012), including studies of T. bostocki(Beatty et al, 2010). Our seasonal (weekly movement) and flow pulse (daily movement) studies found that T. bostocki generally performed larger downstream movements during higher flows and smaller upstream movements during lower flows.…”

Personality-dependent spatial ecology occurs independently from dispersal in wild burbot (Lota lota)

“…Furthermore, only a few authors have investigated the role of personality in other important spatial ecology metrics including HR (Minderman et al 2010), movement (Fraser et al 2001;Chapman et al 2011;Brodersen et al 2012), and site fidelity (Brodersen et al 2012). Indeed, individual differences in movement behaviors are a typical feature of spatial ecology data sets, particularly in fishes (Conrad et al 2011;Taylor and Cooke 2012), which often feature "resident" and "mobile" contingent strategies (Skalski and Gilliam 2000;Fraser et al 2001;Morrissey and Ferguson 2011;Radinger and Wolter 2013). Research on this heterogeneity has tended to focus on internal factors, such as body size and ontogeny, and external environmental cues, such as habitat-suitability, temperature, and light (Lucas and Baras 2001).…”